A technology for selective separation of materials through membranes is used in water treatment such as water purification and treatment of industrial water, re-used water, waste water, and the like. In order to improve productivity of water purification, hollow fiber membranes are generally used as the membranes. A module or filtering apparatus using hollow fiber membranes may have a structure wherein a bundle of hollow fiber membranes is secured to a header and filtered water is collected by the header. A hollow fiber membrane module may be operated in a dipping manner or in a compressive manner which can provide superior capabilities in treatment of produced water despite requirements for a separate system for fluid circulation.
A hollow fiber membrane unit includes a bundle in which plural hollow fiber membranes are arranged. Side portions of one end of each of the hollow fiber membranes are fixed to a header by a potting material, thereby forming a module. In order to prevent an exposed hollow potion of an end of the hollow fiber membrane from being blocked by the potting material, a complex process, such as performing a potting process by introducing a fugitive material that temporarily blocks the end of the hollow fiber membrane and is removed in a subsequent process, spreading the process of introducing the potting material, or introducing a cutting process for partially cutting a potted end of the hollow fiber membrane, is needed in coupling of the hollow fiber membranes to the header.